Nut



J. P. BURKE Sept. 9, 1941.

NUT

2 Sheets-Sheet 1 Original Filed March 6, 1939 Sept. 9, 1941.

J. P. BURKE 2,255,649

NUT

Original Filed March 6, 1939 2 Sheets-Sheet 2 INVENTOR 3/5/2293 W @z/r%e BY Y - ATTORNEY Patented Sept. 9. 1 941 UNITED STATES PATENT OFFICE NUT James P. Burke, Knoxville, Tenn., assignor to Bert L. Quarnstrom and F. L. McLaughlin, both of Detroit, Mich.

3 Claims.

This application is a division of application Serial No. 260,061, filed March 6, 1939.

This invention relates to nuts and has for its object to provide a nut having means for retaining it on one of a pluralityof members to be secured together in order to avoid the necessity of manually holding the nut against rotation when a screw'is inserted therein, and in order that said nut may serve as a locating means for the screw and the members secured to the first member by the screw.

In the fabrication of various constructions, particularly automobile bodies, it is the practice to first secure the nut on one of the plurality of members to be secured together, to avoid the necessity of holding the nut against rotation, and to enable use of a bolt and nut in cases where the fabrication is such as to prevent access to the nut by a wrench. The nut may also serve as alocating means for the members secured together.

The usual practice is to provide a nut and an aperture so shaped that rotation of the nut in the aperture is impossible. After insertion of the nut in the opening a portion thereof is clinched over or riveted to prevent removal from the opening. With such an arrangement it is necessary in the case of fabrication of an automobile body to insert the nuts in apertures in the body panels and to convey the panels to a clinching press where they are individually clinched. This operation is time consuming and expensive, and exposes the panels to damage by deformation or by collision with other articles.

The main object of this invention is to provide a nut capable of retaining itself in an aperture Without clinching or riveting thereof. In this respect a nut is provided having means which coacts with the walls of an aperture receiving the nut to hold the nut against removal ,irom the aperture, and against rotation in the aperture.

Another object is to provide a nut having retaining means for confining a portion of the member to. which it is to be secured in such manner as to induce a high degree of friction tending to prevent removal of the nut from said member.

Another object is to provide a not having a conical recess or seat in one end thereof and means for engaging a portion of a sheet metal member to crowd said portion against said seat and to thereby retain the nut on said member.

Another object is to provide a nut having a stem portion surrounded by a conical seat and adapted to be inserted through art aperture in a sheet metal member, said stem having means thereon for crowding the metal surrounding said opening against said seat to retain the nut on said member, and to induce suflicient friction to prevent rotation of the nut. In this respect the invention teaches alternative means for retaining the nut, in one case inducing friction by a cam-like action and in another by means of screwthreads.

Another object is to provide a nut having coacting retaining means including cam-like elements and embodying means for preventing movement past thehigh point of the cam elements in the presence of an excessive force.

Another object is to provide a nut having coacting means rendered operative by rotation of the nut for securing the nut to a member, and means for preventing rotation in either direction when thecoacting means are operative.

Another object is to provide a nut of this character which is composed of a series of laminations adapted to be distorted by insertion of a screw therein in order that the inherent resiliency of the laminations induces friction tending to prevent removal of the screw.

Other objects and advantages will become more fully apparent as reference is had to the accompanying drawings wherein my invention is illustrated, and in which:

Fig. 1 is a longitudinal section illustrating a plurality of elements secured together;

Fig. 2 is a view taken on the line 2-2 of Fig. 1;

Fig. 3 is a view showing the nut partially in section and partially in elevation;

Fig. 4 is a fragmental elevation illustrating the aperture for receiving the nut;

Fig. 5 is a developed view of the aperture wall,

taken on the line 5--5;

Fig. 6 is a section similar to Fig. 1, illustrating an alternative means for retaining the nut on a panel member;

Fig. 7 illustrates an alternative aperture formation foruse with a nut such as shown in Fig. 6;

Fig. 8 is a section taken on the line Fig. '7;

Fig. 9 is a section of the blank from which the nut in Fig. 6 is formed Fig. 10 is a view similar to Fig. 2, illustrating a variation in the number of nut retaining members; v

Fig'. 11 is a section illustrating a nut formed of a plurality of laminations of sheet-like metal;

I} Fig. 12 is a section illustrating the laminated nut in use;

Figs. 13 and 14 are views taken on lines I3--I3 and I4I4, respectively, of Fig. 11';

Figs. 15 and 16 are sections on lines I5--I5 and I6I6, respectively, of Fig. 12, and

Fig. 17 is a fragmental view illustrating the aperture for receiving the laminated nut.

With reference to Figs. 1 to 5, I designates the main body portion of a nut, of hexagonal or other suitable shape, having a screwthreaded bore 2 extending centrally therethrough. In one end of thebody I is a recess 3 of conical shape, and centrally of the recess, surrounding the bore 2, is a stem 4. The stem 4 has radial arms 5 struck therefrom with their ends in spaced relation to the surface of the conical recess 3.

The element 6, to which the nut is to be se-' cured, has an aperture 1 with radial extensions 8, the aperture 1 having a diameter permiti ting insertion of the stem 4 therein and the extensions 8 being proportioned to permit the ravreverse-direction when the arms 5 are first in serted through the apertures. In other ;words, the high ends of the cams constitute means for direction, when the arms are first inserted in the aperture.

After insertion of the stem 4 into-the aperture I the nut is rotated in the direction of the arrow I and the arms ride against the higher cam portions to create a substantial amount of friction to oppose removal of the nut. The arms .5 also act to compress a substantial portion of ,the element 6 between themselves and the surface of the conical recess 3. To prevent the arms 5 from passing completely over the cams 9 and into register with the next succeeding aperture extensions 8, in the presence of an excessive rotating force, projections II are provided at the higher ends of the cams and function as positive stops.

After the nut has been secured to the element 6 the latter may be placed in any desired fabripreventing rotation of the arms 5in the wrong i cation, and may have any number of elements such as the one I2 secured thereto by a screw I3 whose end engages in the screw threaded bore 2 of the nut.

As shown in Figs. 1 to 5 there are three'arms 5 and three corresponding aperture extensions 8. Thisnumber was chosen for purposes of example and might be varied either by increas-. ing or decreasing the number of arms, as in Fig.

10,,wherein two arms 50. and two aperture ex-' tensions 8a are provided. To prevent retrograde rotation of the nut, depressions IIa are provided into which the arms 5a snap. a

The nut shown in Fig. 6 comprises a main body portion I5 having a central screwthreaded bore Iii, a conical recess I'I in'one end thereof and an externally screwthreaded stem I8 disposed in the recess I'I. Theelement I9 to which the nut is to be secured has a screwthreaded opensurrounding said aperture. is screwed into the aperture 26,. the-threads on the stem tend to compress the concavo convex. formation 2I against the wall oftherecess,

ing 20 and a concavo-convex conical portion 2I1 When thestem Ill-j war lithrough. extensions 31 of :-an' apertur 38 in a which confines the formation 2| and prevents distortion such as would permit stripping of the threads. This relationship also sets up a Jambing or wedging action which induces suificient friction to retain the nut on the element I9. Other elements such as the one 22 are subsequently secured to the element I9 by a screw 23 which engages the nut I5.

It will be noted upon reference to Fig. 6 that the nut I5 is screwed into the aperture 20 from the side opposite to which the screw is screwed into the 'nut. Therefore, if the stem I8 has right hand threads its removal from the aperture 20 will .be caused by rotative movement in the same direction as the movement necessary to screw a screw with right hand threads into'the nut. .Ihus, screwing of the screw into the nut ordinarily tends to loosen the nut, and

to correct this condition the stem I8 is provided with left hand screw threads in the case of a screw having right hand threads. The threads on the screw 23 are shown as right hand threads in Fig. 6, and the threads on the stem I8 are intended to represent left hand threads.

A shown in Fig. 6 the threads on the stem I8 are larger than the threads on the screw 23, which makes it impossible for the nut to loosen of its own accord even though right hand threads are present in both cases. To permit rotation of the nut relative to the threads 20 the nut 'must move lengthwise a distance greater than the lengthwise distance resulting from an equal amount of rotation relative to the screw, which results in a binding action.

With the arrangement shown in Fig. 6 it is necessary to tap the aperture 20 to provide screw threads therein. This operation may be avoided by the construction shown in Figs. 7 and 8, in which case the element I9a has an aperture 20a therein and a slit 24 therein extending radially from the aperture. On one side of the slit 24 the metal is bent upwardly as at 25, and at the other side it is bent downwardly at 26. The metal of the element I9a has less thickness than the distance between two threads and the bent portions 25 and 26 provide a lead for threads in order that the stem I8 may the aperture. U s

In Fig. 9 there is shown a blank I5a from which the nut 5 is made. Afterproviding screwthreads on the stem I 8a thelnut is compressed axially so that the normally flatwall Ila becomes depressed to form theconical recess II. This disposes the screwthrea'ds on the stem I8 within the recess II, after which the bore I6a is tapped to complete the nut.

The nut shown in Figs. llto 17=instead of being solid as in the case of the nut I is composed of a plurality of laminations'30 of sheet metal. The. several laminations 30 are formed by reversely bending 'a continuous strip upon itself itslo thizttezzch lamination is connected at oppos e en I 0 he laminations ono i i thereof. With the exception of the 553 12335 tion 3| which is of special form, the laminations all have control apertures32 and the laminations are so formed that-the several apertures are coaxial. Each lamination is pierced and bent at 3312c providefajscrew lead in order that each aperture wallmay. constitute ,a screw thread.

The uppermost lamination3l is bent to form a conical seat 34 and-an axial'stem35. The stem pierced and-hasfsevered portions bent outyto 1 form armsf'3j6 which are insertable be screwed intopanel or like element 39. Adjacent the aperture 38 the element 39 is bent to form earns 40 against which the arms 36 press when the nut is rotated. The nut has circumferentially elongated slots 4| into which retainer prongs 42 onthe element 38 are pressed by the fingers 36 as they ride against the cams 40. The prongs 42 prevent removal or the nut.

The laminations 30 are' formed of stock having less cross-sectional thickness than the distance between the threads 43 on the screw 44, as may readily be seen upon reference to Figs. 12 and 15. As the screw is screwed into the nut, the bent portions 33 constitute the lead necessary to permit entrance of the thread 43 into the several apertures 32.- As the thread 43 enters the apertures, the several laminations 30 are caused to spread apart, and, therefore, to crowd against the thread walls thus setting up a very substantial locking friction.

What is claimed is:

1. In combination, a sheet member having a preformed concavo-convex portion with an aperture therein, a nut having astem insertabl in said aperture and a concave seat surrounding the stem and receiving the convex portion of said member, and means on said nut tending to expand said convex portion against said seat incident to rotation of the nut in one direction.

2. In combination, a sheet member having a pre-formed concavo-convex portion with an aperture therein, a nut having a stem insertabie in said aperture and a concave seat surrounding the stem and receiving the convex portion of said member, and coacting cam means on the stem and member for clamping said convex portion against said seat incident to rotation of the nut in one direction.

3. In combination, a sheet member having a pre-formed concave-convex portion with an aperture therein, a nut having a stem insertable in said aperture and a concave seat surrounding the stem and receiving the convex portion of said member, means on said nut tending to expand said convex portion against said seat incident to rotation of the nut in one direction, and said nut having a screwthreaded bore with the lead angle opposite to said direction of rotation of said nut.

JAMES P. BURKE. 

